Two trains have collided at Ladbroke Grove near London's Paddington Station.
The accident occurred at 08:11. The trains involved were the 08:06 Thames Trains service from London to Bedwyn in Wiltshire and the 06:03 Great Western 125 from Cheltenham which was approaching Paddington.
Eyewitnesses report that fire has broken out in one of the trains. A spokesperson from the London Fire Brigade confirmed that there are around 70 firefighters at the scene and that they are tackling a fire in one of the carriages. A pall of smoke is said to be covering the area. It is thought that the fire started as a result of a fuel tank being punctured in the lead power car of the IC125
British Transport Police have confirmed that one person was killed and as many as 300 people have been injured. Ten people are said to have suffered severe injuries and 100 people have suffered burns.
A public inquiry is currently being conducted by the Health & Safety Executive into an accident involving another GWT IC125 which occurred two years ago at southall which is on the same stretch of line.
Scotland Yard has set up a phone help line for those concerned about relatives or friends who may have been travelling on the trains